Fix RequestRepeater caching (#21693)

* Fix RequestRepeater caching

* cleanup

Co-authored-by: Comma Device <device@comma.ai>

selfdrive/ui/qt/request_repeater.cc

@@ -15,7 +15,7 @@ RequestRepeater::RequestRepeater(QObject *parent, const QString &requestURL, con
   if (!cacheKey.isEmpty()) {
     prevResp = QString::fromStdString(params.get(cacheKey.toStdString()));
     if (!prevResp.isEmpty()) {
-      QTimer::singleShot(0, [=]() { emit receivedResponse(prevResp); });
+      QTimer::singleShot(500, [=]() { emit receivedResponse(prevResp); });
     }
     QObject::connect(this, &HttpRequest::receivedResponse, [=](const QString &resp) {
       if (resp != prevResp) {
@@ -23,11 +23,5 @@ RequestRepeater::RequestRepeater(QObject *parent, const QString &requestURL, con
         prevResp = resp;
       }
     });
-    QObject::connect(this, &HttpRequest::failedResponse, [=](const QString &err) {
-      if (!prevResp.isEmpty()) {
-        params.remove(cacheKey.toStdString());
-        prevResp = "";
-      }
-    });
   }
 }